Electronic - Free

Proceedings

Out of Print

General notes:

Copies of the papers presented at, or published for DCC are available in
various ways. A paper printed in the proceedings will be available for
purchase in most cases in hard copy as the DCC proceedings. It will in
most cases also be available as an individual paper in PDF format as a
free download via a link below the abstract (where available) It may
also be available on CD-ROM. A paper printed in the proceedings may not
have been presented at the conference. Also a presentation at DCC may
not be in the printed proceedings. In those cases it may be available
on DVD, CD-ROM or as a MP3 download. Links to what is available will be
on the page specific to the particular year's DCC.

Unfortunately, all the video links below have been broken by a change of ISP for the host. The following will take you to an index at You Tube. (hint: the episode number in the broken link may help you find the video).

Abstract:
"Be Smart, Not Strong" this should be the self explaining phrase of the QRP term in amateur radio.
Low power operation is always more difficult than using hundreds or thousands of watts RF power.
But the smile on your face after the first thousands miles long QSO, using portions of one watt is
worth the challenge! QRP enthusiasts instead of spending time and money on increasing power
capabilities of its station prefer a smarter way: to learn about new modulations and coding techniques
and applying them in everyday HAM operation practice.

Nowadays one of the most impressive QRP mode is Joe Taylor, K1JT's [8] WSPR [9] (pronounced
"whisper"). WSPR stands for "Weak Signal Propagation Reporter". Programs written for WSPR mode
designed for sending and receiving low-power transmissions to test propagation paths on the MF and
HF and recently UHF bands. Users with internet access can watch results in real time at wsprnet.org

The QRPi board (or shield as referred by the community today) is an inexpensive way of turning a
Raspberry Pi single-board computer into a QRP transmitter.

Abstract:
The Internet has largely replaced shortwave radio for the broadcast of news and
information across international boundaries. A growing number of countries, however, are
blocking Internet content from abroad. As a possible workaround, digital text modes familiar to
the amateur radio community can be used to broadcast news via existing shortwave transmitters
and can be received on any shortwave radio, but software is required to decode the text. VOA
Radiogram is a weekly Voice of America program experimenting with text and images through
a shortwave broadcast transmitter

Abstract:
Mesh technology has been around for over ten years. Over the past two years developers on the
AREDN. team have advanced the art by porting Broadband-Hamnet.s extremely popular mesh
firmware to the Ubiquiti airMAX line of commercial Wireless ISP routers. This has literally changed
the complexion of mesh implementations from an experimental, hobby-oriented, novelty into a viable
alternative network suitable for restoring some degree of Inter/intra-net connectivity .when all else
fails..

More recently, the developers of this software have kicked-off a new project, AREDN, focused on
taking this technology to the next level in EMCOMM communications.

This paper begins with an introduction to the AREDN Project and mesh networking and concludes
with a roadmap for the Project.s future. It dives into implementation techniques and considerations as
well as avoidable pitfalls.

Abstract:
We present simulations of conventional quadrature amplitude modulation (QAM) and Feher-QAM to
estimate the bandwidth improvement for Feher-QAM. We show more than a 10% improvement
(reduction) in bandwidth for Feher-QAM over conventional QAM. We also show the power spectral
density for Feher-QAM has a much faster convergence than conventional QAM.

Abstract:
The old technology of analog-ATV suffers from susceptibility to snow and
multi-path ghost images. Digital-ATV (DATV) using new technologies like
digital modulation, and Forward Error Correction (FEC) can result in
robust video reception where analog-ATV fails, as well as providing more
narrow bandwidths on the ham bands. This presentation will review
progress by the DATV-Express Project Team since DCC2014. These new
efforts include:

Making the exciter more portable by Hardkernel ODROID U3
Single-Board-Computer

Measuring the Ionosphere at vertical incidence using Hermes,
Alex, and Munin Open HPSDR and Gnuradio.
by
Tom McDermott, N5EG

Abstract:
This paper describes a monostatic method for measuring the vertical virtual height and the vertical
velocity of the F-layer of the ionosphere. The equipment is simple and relatively low power, it uses the
Open HPSDR Hermes transceiver module, Munin broadband Power Amplifier (PA), and Alex RF filter
module. The antennas consist of a 40m dipole and antenna tuner for transmit and an active receive
loop antenna. The software real-time processing (reception, windowing, and correlation) is done using
Gnuradio on a Linux PC, followed by post-processing using a Python program (multiple sweep
integration and plotting).

Abstract:
The popularity of low cost PCs and tablets with substantial DSP processing power and an increasing
awareness of digital signal processing in the amateur community have created an explosion of digital
modes. Some of the challenges this poses are lack of portability, inconsistent .virtual TNC. interfaces
and protocols optimized for single uses. ARDOP is a new protocol development which was targeted to
address these challenges. The development started in 2014 and Alpha testing of the ARDOP_Win
TNC (Windows version) was begun in April 2015. From the beginning the protocol was designed to
cover a wide spectrum of amateur uses and be fully documented with open sourced code to encourage
learning, experimentation, evolution and portability to other platforms both software and hardware.
Key words: ARQ, FEC, 4FSK, 8FSK, 16FSK, 4PSK, 8PSK, WINMOR, cyclic prefix, bandwidth
negotiation, automatic timing, open source and sound card protocols.

Abstract:
The design of a standalone battery powered Software
Defined Radio (SDR) is presented. Three
rounds of prototypes were designed, built, and
tested over the last three years. The hardware architecture
of the newest design is detailed, with
the goal of getting the device into the field to
build real RF links. The software stack, from
the high-level websocket user interface down to
the embedded Linux operating system are discussed.
Finally, the latest work on the Field Programmable
Gate Array (FPGA) modem are presented,
including optimization work that drastically
improves simulation performance.

Abstract:
The SatNOGS, or Satellite Network Open
Ground Stations, project promotes and supports free and
open space applications. It seeks to solve the problem
of connecting many satellite users/observers to many
ground station operators. Modern open software, web,
and hardware techniques are used in implementing the
Network, Database, Client, and Ground Station subprojects.
Modularity in all the systems promotes the
dual-use of ground stations by not interfering with local
operation while utilizing the great amount of time a
civilian, non-commercial ground station would otherwise
sit idle.